Serverless: Best Practices for Architecting a Serverless System


Serverless architecture is becoming an exciting option for many cloud architectects considering its specific benefits. Also known as function-as-a-service, serverless architecture is enabling developers to deploy their cloud applications without requiring them to manage any servers.

However, there aren’t any set of defined rules to follow when it comes to developing a serverless system. There has been a lot of debates going on from time to time about the best practices though there are very few which are widely accepted. And not having predefined practices makes it hard for organizations to leverage the exact benefits that serverless promises.

If you are building an application keeping in mind scalability, performance and security, you will be required to follow some of the common serverless practices. Let’s discuss them in this article.

1. Develop a single purpose Stateless Function


By default, the recommended practice is to write single-purpose code for the function since functions are stateless and exist for a limited duration only. By doing this, you are limiting the execution time which is directly proportional to the overall costing.

Also, functions with single-purpose code are easier to test, deploy and release. This also improves software agility. The problem with multi-purpose functions running your entire application is when you end up scaling an entire application rather than scaling a particular functionality.

For example, your application has a function which serves two applications, where first serves some thousands of requests whereas the second one serves some hundreds request. Now imagine a situation where you’re required to optimize this function, you will have to do it keeping the requirements of both the apps. Instead, split the function and make a separate one for both the applications and simplify the process.

2. Create powerful & thicker frontend

Poor frontend requires lot of back-and-forth from frontend to backend. Due to this, the processes start lagging with increases latency. To tackle this, the best practice would be to separate frontend from the backend.

Executing a more complex business functionality at the frontend especially through rich client-side application framework can potentially help in reducing the cost by minimizing the function calls and execution times. The best way to do it would to completely decouple backend logic from the frontend while not compromising on security. At the same time, this allows more services to be accessed from the frontend. This will result in better application performance and richer user experience.

3. Design trigger based event-driven pattern

As discussed in the above point, developing a decoupled application can go a long way in terms of scalability. Apart from that, it can help you reduce the interdependencies within functions so that failures do not impact other components and in enabling data synchronizations across the web application layer.

And hence, designing a push-based and event-driven architecture patterns where a chain of events propagate without any user input. This form of event-driven patterns gives the serverless its power: scalability to an architecture.

4. Identifying performance bottlenecks

The key benefit of serverless architecture is that developers can concentrate on writing code rather than focusing on how and where to run the code. However, when it comes to functions, understanding the performance bottlenecks is a bit tricky subject. The lack of familiar monitoring environment than the traditional system makes it hard for the Devs to understand why the particular function is taking long to execute.

For example, functions calling other functions. By incorporating such antipatterns, you not only double your overall cost but it also makes the debugging more complex while abstracting the isolation value from your functions. The endpoint, identifying the performance bottlenecks may take a while but it is highly critical for seamless customer experience.

5. Incorporating Standard Security Mechanism

Functions are governed by different security policies. This makes it important for you to incorporate proper security mechanism for the API Gateway and functions both. The IAM policy management will include aspects like access controls, identity and access management, authentication management, encryption & decryption and much more.

For example, you may violate this best practice by employing external libraries. Using external libraries will also result in more cold starts since more libraries need more instantiating. In terms of security, more libraries equal to more vulnerabilities. This makes it highly critical for you to follow the Principle of Least Privilege.

6. Using third party services

While you’re developing a software application, it might not be a recommended solution to build every functionality on your own. Doing so might add a lot more complexities. In the serverless ecosystem, lately, there has been the development of exciting enterprise tools for various services like logging, monitoring, etc.

The current tools that you are using might not be compatible considering the event-driven approach of serverless architecture. Choosing the right third-party tools will be the key for enterprises for reaping out the maximum benefits from serverless.


With the right processes in the architectural practice, serverless may present to your organization an exit strategy from the legacy infrastructure and make the most out of the public serverless offerings. Serverless is still undergoing through the cycle before the mainstream adoption happens on the large scale.

Till the time we have a standard set of processes to follow, incorporating the best practices can help you take the basic advantage of serverless computing, i.e reduced time-to-market, enhanced scalability and cost benefits.



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